Parents are being urged to take more responsibility over children's use of school-issue computer equipment – outside the classroom.
Pupils as young as eight have been caught using iPads to play zombie shooting games and message one another in the early hours of the morning.
Dozens of schools across the county offer hire-purchase schemes through Apple so parents can buy their youngsters the latest tablet computers at an affordable price.
This includes Hartsholme Academy, in Lincoln, which insists parents sign a contract to ensure their children's iPad usage is properly monitored at home.
But complaints are being made that some parents are not taking the appropriate responsibility.
Sarah Curtis, from Birchwood Avenue, has an eight-year-old daughter Kayleigh, who attends Hartsholme Academy.
She said that after Kayleigh has gone to bed, she will continue to receive messages through the night from children whose parents are not paying enough attention.
"One girl has been messaging my daughter after midnight and her parents don't know about it," she explained.
"Obviously, my daughter is asleep in bed but we hear her iPad going off.
"Some parents just aren't keeping an eye on what their kids are doing.
"I check Kayleigh's iPad every day to make sure she doesn't have anything silly on there and we've put an age restriction on as well.
"But other parents just don't seem to be acting in the same way. It's not just disruptive to their own children, but disruptive to others as well.
"The iPads are good when it comes to helping their learning with things like maths, and all the educational apps they can get, but not for all these shooting games and social messaging sites."
Hartsholme Academy has a "net nanny" programme which runs through the school's internet network, filtering content and restricting what can be downloaded.
This system will also affect how the iPads are used at home from Easter.
A letter has been sent home by the school urging parents to introduce proper controls, while fortnightly spot-checks are being made by teachers as well.
Head teacher Carl Jarvis revealed that the school had banned all messaging apps.
He said: "We had a full inspection when complaints were made and we've banned all messaging.
"We've discussed with the children and parents learning opportunities with the iPads and given extra lessons on e-safety.
"Parents have told us how their children have grown in confidence and eagerness to do their homework since we introduced the iPads.
"It's up to the parents now to police how their children use the iPads outside of school and they sign a contract when they take out the scheme to say this.
"We can't say what children can and can't do at home, so that's why we have the contract. We hold our side of the bargain here and there's nothing inappropriate happening in the school.
"The whole idea with iPads is that they raise academic achievement – and it does so massively.
"We've done the research and achievement has gone through the roof."